Please check out message 22 for some help on these matters
http://www.lsm.org/living-stream-ministry-radio/audio/ephesians.html 

(Ephesians 2:11-18)For he himself is our peace, who has made the two one and has destroyed the barrier, the dividing wall of hostility, by aboloshing in his flesh the law with its comandments and regulations. His purpose was to create in himself one new man out of the two, thus making peace, and in this one body to reconcile both of them to God through the cross, by which he put to death their hostility. He came and preached peace to you who were far away and peace to those who were near. For through him we both have access to the Father by one Spirit.
Christs death put an ennnd to all the regulationns of the old testament regarding sacrifices etc. because noone could live by them. His death was our atonement for sin and gave us a bridge to the Father. The two were the jews and gentiles, which were alienated from each other until Paul was sent to the gentiles to preach the word to them thus bringing them together in the faith as one. Just as each of us are the church and the church is the body of Christ, so the Jews and Gentiles are now one in faith and family with God. Does this help any? God Bless